This patch adds loading, stamp checking and initialization of modules.
The init function of dynamic module is no longer directly called as
__attribute__((constructor)) in static linked version, it is called
only after passed the checking of presense of stamp symbol:
qemu_stamp_$RELEASEHASH
where $RELEASEHASH is generated by hashing version strings and content
of configure script.
With this, modules built from a different tree/version/configure will
not be loaded.
The module loading code requires gmodule-2.0.
Modules are searched under
- CONFIG_MODDIR
- executable folder (to allow running qemu-{img,io} in the build
directory)
- ../ of executable folder (to allow running system emulator in the
build directory)
Modules are linked under their subdir respectively, then copied to top
level of build directory for above convinience, e.g.:
$(BUILD_DIR)/block/curl.so -> $(BUILD_DIR)/block-curl.so
Signed-off-by: Paolo Bonzini <pbonz...@redhat.com>
Signed-off-by: Fam Zheng <f...@redhat.com>
---
Makefile | 3 ++
configure | 49 ++++++++++++-----
include/qemu/module.h | 18 ++++++-
module-common.c | 10 ++++
rules.mak | 10 ++--
scripts/create_config | 14 +++++
util/module.c | 145 +++++++++++++++++++++++++++++++++++++++++++++++++-
7 files changed, 229 insertions(+), 20 deletions(-)
create mode 100644 module-common.c
diff --git a/Makefile b/Makefile
index 9de66cb..670ce44 100644
--- a/Makefile
+++ b/Makefile
@@ -203,6 +203,9 @@ Makefile: $(version-obj-y) $(version-lobj-y)
libqemustub.a: $(stub-obj-y)
libqemuutil.a: $(util-obj-y) qapi-types.o qapi-visit.o
+block-modules = $(foreach o,$(block-obj-m),"$(basename $(subst /,-,$o))",) NULL
+util/module.o-cflags = -D'CONFIG_BLOCK_MODULES=$(block-modules)'
+
######################################################################
qemu-img.o: qemu-img-cmds.h
diff --git a/configure b/configure
index a6a626f..0da1253 100755
--- a/configure
+++ b/configure
@@ -677,7 +677,8 @@ for opt do
;;
--disable-debug-info)
;;
- --enable-modules) modules="yes"
+ --enable-modules)
+ modules="yes"
;;
--cpu=*)
;;
@@ -1130,7 +1131,7 @@ Advanced options (experts only):
--libdir=PATH install libraries in PATH
--sysconfdir=PATH install config in PATH$confsuffix
--localstatedir=PATH install local state in PATH (set at runtime on
win32)
- --with-confsuffix=SUFFIX suffix for QEMU data inside datadir and sysconfdir
[$confsuffix]
+ --with-confsuffix=SUFFIX suffix for QEMU data inside
datadir/libdir/sysconfdir [$confsuffix]
--enable-modules enable modules support
--enable-debug-tcg enable TCG debugging
--disable-debug-tcg disable TCG debugging (default)
@@ -2346,14 +2347,32 @@ if test "$mingw32" = yes; then
else
glib_req_ver=2.12
fi
-if $pkg_config --atleast-version=$glib_req_ver gthread-2.0; then
- glib_cflags=`$pkg_config --cflags gthread-2.0`
- glib_libs=`$pkg_config --libs gthread-2.0`
- CFLAGS="$glib_cflags $CFLAGS"
- LIBS="$glib_libs $LIBS"
- libs_qga="$glib_libs $libs_qga"
-else
- error_exit "glib-$glib_req_ver required to compile QEMU"
+
+for i in gthread-2.0 gmodule-2.0; do
+ if $pkg_config --atleast-version=$glib_req_ver $i; then
+ glib_cflags=`$pkg_config --cflags $i`
+ glib_libs=`$pkg_config --libs $i`
+ CFLAGS="$glib_cflags $CFLAGS"
+ LIBS="$glib_libs $LIBS"
+ libs_qga="$glib_libs $libs_qga"
+ else
+ error_exit "glib-$glib_req_ver $i is required to compile QEMU"
+ fi
+done
+
+##########################################
+# SHA command probe for modules
+if test "$modules" = yes; then
+ shacmd_probe="sha1sum sha1 shasum"
+ for c in $shacmd_probe; do
+ if which $c &>/dev/null; then
+ shacmd="$c"
+ break
+ fi
+ done
+ if test "$shacmd" = ""; then
+ error_exit "one of the checksum commands is required to enable
modules: $shacmd_probe"
+ fi
fi
##########################################
@@ -3628,6 +3647,7 @@ if test "$mingw32" = "yes" ; then
fi
qemu_confdir=$sysconfdir$confsuffix
+moddir=$libdir$confsuffix
qemu_datadir=$datadir$confsuffix
qemu_localedir="$datadir/locale"
@@ -3718,6 +3738,7 @@ echo "Install prefix $prefix"
echo "BIOS directory `eval echo $qemu_datadir`"
echo "binary directory `eval echo $bindir`"
echo "library directory `eval echo $libdir`"
+echo "module directory `eval echo $moddir`"
echo "libexec directory `eval echo $libexecdir`"
echo "include directory `eval echo $includedir`"
echo "config directory `eval echo $sysconfdir`"
@@ -3849,6 +3870,7 @@ echo all: >> $config_host_mak
echo "prefix=$prefix" >> $config_host_mak
echo "bindir=$bindir" >> $config_host_mak
echo "libdir=$libdir" >> $config_host_mak
+echo "moddir=$moddir" >> $config_host_mak
echo "libexecdir=$libexecdir" >> $config_host_mak
echo "includedir=$includedir" >> $config_host_mak
echo "mandir=$mandir" >> $config_host_mak
@@ -3867,9 +3889,6 @@ echo "libs_softmmu=$libs_softmmu" >> $config_host_mak
echo "ARCH=$ARCH" >> $config_host_mak
-if test "$modules" = "yes"; then
- echo "CONFIG_MODULES=y" >> $config_host_mak
-fi
if test "$debug_tcg" = "yes" ; then
echo "CONFIG_DEBUG_TCG=y" >> $config_host_mak
fi
@@ -3991,6 +4010,10 @@ echo "TARGET_DIRS=$target_list" >> $config_host_mak
if [ "$docs" = "yes" ] ; then
echo "BUILD_DOCS=yes" >> $config_host_mak
fi
+echo "CONFIG_STAMP=`(echo $qemu_version; echo $pkgversion; cat $0) | $shacmd -
| cut -f1 -d\ `" >> $config_host_mak
+if test "$modules" = "yes"; then
+ echo "CONFIG_MODULES=y" >> $config_host_mak
+fi
if test "$sdl" = "yes" ; then
echo "CONFIG_SDL=y" >> $config_host_mak
echo "SDL_CFLAGS=$sdl_cflags" >> $config_host_mak
diff --git a/include/qemu/module.h b/include/qemu/module.h
index c4ccd57..d6da64f 100644
--- a/include/qemu/module.h
+++ b/include/qemu/module.h
@@ -14,11 +14,26 @@
#ifndef QEMU_MODULE_H
#define QEMU_MODULE_H
+#ifdef BUILD_DSO
+void DSO_STAMP_FUN(void);
+/* This is a dummy symbol to identify a loaded DSO as a QEMU module, so we can
+ * distinguish "version mismatch" from "not a QEMU module", when the stamp
+ * check fails during module loading */
+void qemu_module_dummy(void);
+
+#define module_init(function, type) \
+static void __attribute__((constructor)) do_qemu_init_ ## function(void) \
+{ \
+ register_dso_module_init(function, type); \
+}
+#else
/* This should not be used directly. Use block_init etc. instead. */
#define module_init(function, type) \
-static void __attribute__((constructor)) do_qemu_init_ ## function(void) { \
+static void __attribute__((constructor)) do_qemu_init_ ## function(void) \
+{ \
register_module_init(function, type); \
}
+#endif
typedef enum {
MODULE_INIT_BLOCK,
@@ -34,6 +49,7 @@ typedef enum {
#define type_init(function) module_init(function, MODULE_INIT_QOM)
void register_module_init(void (*fn)(void), module_init_type type);
+void register_dso_module_init(void (*fn)(void), module_init_type type);
void module_call_init(module_init_type type);
diff --git a/module-common.c b/module-common.c
new file mode 100644
index 0000000..50c6750
--- /dev/null
+++ b/module-common.c
@@ -0,0 +1,10 @@
+#include "config-host.h"
+#include "qemu/module.h"
+
+void qemu_module_dummy(void)
+{
+}
+
+void DSO_STAMP_FUN(void)
+{
+}
diff --git a/rules.mak b/rules.mak
index fb3482b..3037b1f 100644
--- a/rules.mak
+++ b/rules.mak
@@ -69,13 +69,14 @@ endif
%.o: %.dtrace
$(call quiet-command,dtrace -o $@ -G -s $<, " GEN $(TARGET_DIR)$@")
-%$(DSOSUF): QEMU_CFLAGS += -fPIC
+%$(DSOSUF): QEMU_CFLAGS += -fPIC -DBUILD_DSO
%$(DSOSUF): LDFLAGS += $(LDFLAGS_SHARED)
-%$(DSOSUF): %.mo libqemustub.a
+%$(DSOSUF): %.mo libqemustub.a module-common.o
$(call LINK,$^)
+ @# Copy to build root so modules can be loaded when program started
without install
+ $(if $(findstring /,$@),$(call quiet-command,cp $@ $(subst /,-,$@), "
CP $(subst /,-,$@)"))
.PHONY: modules
-modules:
%.mo:
$(call quiet-command,touch $@," GEN $(TARGET_DIR)$@")
@@ -206,7 +207,8 @@ $(foreach o,$(filter %.o,$($1)),
$(eval $(patsubst %.o,%.mo,$o)-objs := $o))
$(foreach o,$(filter %.mo,$($1)),$(eval \
$o: $($o-objs)))
-$(eval modules-m += $(patsubst %.o,%.mo,$($1)))
+$(eval t := $(patsubst %.o,%.mo,$($1)))
+$(foreach o,$t,$(eval modules-m += $o)))
endef
define unnest-vars
diff --git a/scripts/create_config b/scripts/create_config
index b1adbf5..d7ba61d 100755
--- a/scripts/create_config
+++ b/scripts/create_config
@@ -26,6 +26,17 @@ case $line in
# save for the next definitions
prefix=${line#*=}
;;
+ moddir=*)
+ eval "moddir=\"${line#*=}\""
+ echo "#define CONFIG_MODDIR \"$moddir\""
+ ;;
+ CONFIG_STAMP=*)
+ echo "#define DSO_STAMP_FUN qemu_stamp_${line#*=}"
+ echo "#define DSO_STAMP_FUN_STR \"qemu_stamp_${line#*=}\""
+ ;;
+ CONFIG_MODULES=*)
+ echo "#define CONFIG_MODULES \"${line#*=}\""
+ ;;
CONFIG_AUDIO_DRIVERS=*)
drivers=${line#*=}
echo "#define CONFIG_AUDIO_DRIVERS \\"
@@ -104,6 +115,9 @@ case $line in
value=${line#*=}
echo "#define $name $value"
;;
+ DSOSUF=*)
+ echo "#define HOST_DSOSUF \"${line#*=}\""
+ ;;
esac
done # read
diff --git a/util/module.c b/util/module.c
index 7acc33d..207d867 100644
--- a/util/module.c
+++ b/util/module.c
@@ -13,6 +13,8 @@
* GNU GPL, version 2 or (at your option) any later version.
*/
+#include <stdlib.h>
+#include <gmodule.h>
#include "qemu-common.h"
#include "qemu/queue.h"
#include "qemu/module.h"
@@ -21,13 +23,16 @@ typedef struct ModuleEntry
{
void (*init)(void);
QTAILQ_ENTRY(ModuleEntry) node;
+ module_init_type type;
} ModuleEntry;
typedef QTAILQ_HEAD(, ModuleEntry) ModuleTypeList;
static ModuleTypeList init_type_list[MODULE_INIT_MAX];
-static void init_types(void)
+static ModuleTypeList dso_init_list;
+
+static void init_lists(void)
{
static int inited;
int i;
@@ -40,6 +45,8 @@ static void init_types(void)
QTAILQ_INIT(&init_type_list[i]);
}
+ QTAILQ_INIT(&dso_init_list);
+
inited = 1;
}
@@ -48,7 +55,7 @@ static ModuleTypeList *find_type(module_init_type type)
{
ModuleTypeList *l;
- init_types();
+ init_lists();
l = &init_type_list[type];
@@ -62,20 +69,154 @@ void register_module_init(void (*fn)(void),
module_init_type type)
e = g_malloc0(sizeof(*e));
e->init = fn;
+ e->type = type;
l = find_type(type);
QTAILQ_INSERT_TAIL(l, e, node);
}
+void register_dso_module_init(void (*fn)(void), module_init_type type)
+{
+ ModuleEntry *e;
+
+ init_lists();
+
+ e = g_malloc0(sizeof(*e));
+ e->init = fn;
+ e->type = type;
+
+ QTAILQ_INSERT_TAIL(&dso_init_list, e, node);
+}
+
+static void module_load(module_init_type type);
+
void module_call_init(module_init_type type)
{
ModuleTypeList *l;
ModuleEntry *e;
+ module_load(type);
l = find_type(type);
QTAILQ_FOREACH(e, l, node) {
e->init();
}
}
+
+#ifdef CONFIG_MODULES
+static int module_load_file(const char *fname)
+{
+ GModule *g_module;
+ void (*sym)(void);
+ const char *dsosuf = HOST_DSOSUF;
+ int len = strlen(fname);
+ int suf_len = strlen(dsosuf);
+ ModuleEntry *e, *next;
+ int ret;
+
+ if (len <= suf_len || strcmp(&fname[len - suf_len], dsosuf)) {
+ /* wrong suffix */
+ ret = -EINVAL;
+ goto out;
+ }
+ if (access(fname, F_OK)) {
+ ret = -ENOENT;
+ goto out;
+ }
+
+ assert(QTAILQ_EMPTY(&dso_init_list));
+
+ g_module = g_module_open(fname, G_MODULE_BIND_LAZY | G_MODULE_BIND_LOCAL);
+ if (!g_module) {
+ fprintf(stderr, "Failed to open module: %s\n",
+ g_module_error());
+ ret = -EINVAL;
+ goto out;
+ }
+ if (!g_module_symbol(g_module, DSO_STAMP_FUN_STR, (gpointer *)&sym)) {
+ fprintf(stderr, "Failed to initialize module: %s\n",
+ fname);
+ /* Print some info if this is a QEMU module (but from different build),
+ * this will make debugging user problems easier. */
+ if (g_module_symbol(g_module, "qemu_module_dummy", (gpointer *)&sym)) {
+ fprintf(stderr,
+ "Note: only modules from the same build can be loaded.\n");
+ }
+ g_module_close(g_module);
+ ret = -EINVAL;
+ } else {
+ QTAILQ_FOREACH(e, &dso_init_list, node) {
+ register_module_init(e->init, e->type);
+ }
+ ret = 0;
+ }
+
+ QTAILQ_FOREACH_SAFE(e, &dso_init_list, node, next) {
+ QTAILQ_REMOVE(&dso_init_list, e, node);
+ g_free(e);
+ }
+out:
+ return ret;
+}
+#endif
+
+void module_load(module_init_type type)
+{
+#ifdef CONFIG_MODULES
+ char *fname = NULL;
+ const char **mp;
+ static const char *block_modules[] = {
+ CONFIG_BLOCK_MODULES
+ };
+ char *exec_dir;
+ char *dirs[3];
+ int i = 0;
+ int ret;
+
+ if (!g_module_supported()) {
+ fprintf(stderr, "Module is not supported by system.\n");
+ return;
+ }
+
+ switch (type) {
+ case MODULE_INIT_BLOCK:
+ mp = block_modules;
+ break;
+ default:
+ /* no other types have dynamic modules for now*/
+ return;
+ }
+
+ exec_dir = qemu_exec_dir(NULL);
+ dirs[i++] = g_strdup_printf("%s", CONFIG_MODDIR);
+ dirs[i++] = g_strdup_printf("%s/..", exec_dir ? : "");
+ dirs[i++] = g_strdup_printf("%s", exec_dir ? : "");
+ assert(i == ARRAY_SIZE(dirs));
+ g_free(exec_dir);
+ exec_dir = NULL;
+
+ for ( ; *mp; mp++) {
+ for (i = 0; i < ARRAY_SIZE(dirs); i++) {
+ fname = g_strdup_printf("%s/%s%s", dirs[i], *mp, HOST_DSOSUF);
+ ret = module_load_file(fname);
+ /* Try loading until loaded a module file */
+ if (!ret) {
+ break;
+ }
+ g_free(fname);
+ fname = NULL;
+ }
+ if (ret == -ENOENT) {
+ fprintf(stderr, "Can't find module: %s\n", *mp);
+ }
+
+ g_free(fname);
+ }
+
+ for (i = 0; i < ARRAY_SIZE(dirs); i++) {
+ g_free(dirs[i]);
+ }
+
+#endif
+}
--
1.8.5.3
